-void file_read(struct main_file *fi, byte *buf, uns len);
-void file_write(struct main_file *fi, byte *buf, uns len);
-void file_set_timeout(struct main_file *fi, sh_time_t expires);
+void file_read(struct main_file *fi, void *buf, uns len);
+void file_write(struct main_file *fi, void *buf, uns len);
+void file_set_timeout(struct main_file *fi, timestamp_t expires);
+void file_close_all(void); /* Close all known main_file's; frequently used before fork() */